fix(fee-utils): replace hardcoded XLM_PRICE with live useTokenPrice lib/fee-utils.ts hardcoded XLM_PRICE = 0.12 as the default for USD fee estimates. This value becomes stale as the real XLM/USD price moves, causing the displayed fee-in-USD to be arbitrarily wrong. Changes: - Remove the XLM_PRICE constant from fee-utils.ts - Make xlmPrice an optional param (undefined -> estimatedUsd omitted) - Pass the live usdPrice from useTokenPrice('XLM') at every call site: * components/streams/create-confirmation.tsx * app/app/stream/[id]/page.tsx (WithdrawDialog + CancelDialog) Closes #288

Author: brightfootlimited-collab

app/app/stream/[id]/page.tsx

@@ -60,6 +60,7 @@ import {
 import { explorerUrl } from "@/lib/stellar";
 import { useNetwork } from "@/components/providers/network-provider";
 import { useAutoWithdraw } from "@/hooks/use-auto-withdraw";
+import { useTokenPrice } from "@/hooks/use-token-price";
 import { UnlockChart } from "@/components/streams/unlock-chart";
 import { StreamTimeline } from "@/components/streams/stream-timeline";
 import { DownloadReceiptButton } from "@/components/streams/download-receipt-button";
@@ -144,6 +145,7 @@ function WithdrawDialog({
 }) {
   const { withdraw, pending, error } = useContract();
   const { network } = useNetwork();
+  const { usdPrice: xlmPrice } = useTokenPrice("XLM");
   const [inputAmount, setInputAmount] = useState("");
   const [showFeeEstimate, setShowFeeEstimate] = useState(false);
 
@@ -155,7 +157,7 @@ function WithdrawDialog({
 
   // Calculate estimated fees
   const estimatedFee = TYPICAL_FEES.withdraw.typical;
-  const feeBreakdown = calculateFeeBreakdown(estimatedFee);
+  const feeBreakdown = calculateFeeBreakdown(estimatedFee, xlmPrice ?? undefined);
   const withdrawFeeHigh = isHighFee(
     estimatedFee,
     TYPICAL_FEES.withdraw.typical,
@@ -284,10 +286,11 @@ function CancelDialog({
   const { cancel, pending, error } = useContract();
   const { network } = useNetwork();
   const router = useRouter();
+  const { usdPrice: xlmPrice } = useTokenPrice("XLM");
   const [showFeeEstimate, setShowFeeEstimate] = useState(false);
 
   const estimatedFee = TYPICAL_FEES.cancel.typical;
-  const feeBreakdown = calculateFeeBreakdown(estimatedFee);
+  const feeBreakdown = calculateFeeBreakdown(estimatedFee, xlmPrice ?? undefined);
   const cancelFeeHigh = isHighFee(estimatedFee, TYPICAL_FEES.cancel.typical);
 
   async function handleCancel() {

components/streams/create-confirmation.tsx

@@ -16,6 +16,7 @@ import {
   shortenAddress,
 } from "@/lib/stream-utils";
 import { calculateFeeBreakdown, TYPICAL_FEES } from "@/lib/fee-utils";
+import { useTokenPrice } from "@/hooks/use-token-price";
 import type { TokenInfo } from "@/types/stream";
 
 interface ConfirmationProps {
@@ -60,11 +61,17 @@ export function CreateConfirmation({
 }: ConfirmationProps) {
   const rate = formatRate(amountPerSecond, token.decimals, token.symbol);
 
+  // Fetch live XLM/USD price for fee USD estimate
+  const { usdPrice: xlmPrice } = useTokenPrice("XLM");
+
   // Calculate fee breakdown if estimate is available
   const estimatedFeeStroops = feeEstimate
     ? Math.ceil(parseFloat(feeEstimate) * 1e7)
     : TYPICAL_FEES.createStream.typical;
-  const feeBreakdown = calculateFeeBreakdown(estimatedFeeStroops);
+  const feeBreakdown = calculateFeeBreakdown(
+    estimatedFeeStroops,
+    xlmPrice ?? undefined,
+  );
 
   return (
     <Dialog open={open} onOpenChange={(o) => !o && !pending && onCancel()}>

lib/fee-utils.ts

@@ -5,25 +5,26 @@ export interface FeeBreakdown {
   estimatedUsd?: number;
 }
 
-const XLM_PRICE = 0.12; // Average XLM price in USD for estimation
-
 /**
  * Calculate fee breakdown from transaction simulation
  * @param minResourceFee Minimum resource fee from simulation in stroops
- * @param xlmPrice Current XLM price in USD (optional)
+ * @param xlmPrice Current XLM/USD price. Pass the live value from useTokenPrice;
+ *                 omit (or pass undefined) when no price is available and USD
+ *                 estimate should be suppressed.
  * @returns Fee breakdown: base estimate, safety buffer, and total
  */
 export function calculateFeeBreakdown(
   minResourceFee: number,
-  xlmPrice: number = XLM_PRICE,
+  xlmPrice?: number,
 ): FeeBreakdown {
   // Apply 15% buffer to ensure inclusion
   const bufferMultiplier = 1.15;
   const totalFee = Math.ceil(minResourceFee * bufferMultiplier);
   const bufferFee = totalFee - minResourceFee;
 
   const totalXlm = totalFee / 1e7;
-  const estimatedUsd = totalXlm * xlmPrice;
+  const estimatedUsd =
+    xlmPrice !== undefined ? totalXlm * xlmPrice : undefined;
 
   return {
     minFee: minResourceFee,